I'm currently building an intranet site for a customer. There a about 30 different departments involved. Each of them has its own IP address range. A few departments want to share a calendar and a few documents which the others are not allowed to access. The content itself (posts, pages, etc., including the theme) should be the same for all departments.
I thought of setting up a WP multisite with two different sites which would be almost identical except for the calendar and documents. When it comes to accessing the site I thought of redirecting the users based on their origin network so no user knows about the different sites. The problem is that I need some advise on how to accomplish that. Apache's rewrite module is an option but I don't know much about it. May be there is an easier way which I don't know yet. Any advise is welcome.
Thanks in advance, Bastian